I've got a few questions about the courier global
filters (the ones described in courierfilter(8))
1. what is the order that the global filters are run
Why does it matter?
2. are they run at the same time, or one at a time?
One at a time.
3. are all the filters run ? The documentation states
that if at least one filter rejects the message, the
message should be rejected. That makes me wonder if
Courier runs all the filters
Well, if one filter rejects the message there's no reason to run the rest of
I noticed that a filter receives the filename of
the message, and a control file that contains sender
informations, remote IPs, etc.
4. What is the format of the envelope file, and how
stable is this format?
There's some documentation on www.courier-mta.org
5. Is the filter allowed to alter the message file?